TEST POINT 27 TEST 24 COAG
3.4 TEST PROCEDURES
The following paragraphs define the test equipment and procedures required to maintain the PerFect TCS II.
A Test Equipment Required
(1) Oscilloscope, Tektronix Model TDS1001B or equivalent with 100X attenuator probe.
(2) True RMS Multimeter, Fluke model 177 or equivalent.
(3) Thermocouple RF Ammeter, Simpson model 1339 or equivalent, 0 to 500 mA, +/ - 2% full scale accuracy. (This is the preferred factory instrument for measurements pertaining to output power. An oscilloscope may be used as an alternative if an RF Ammeter is not available. )
(4) 600 Ohm (100W) ±5% Non-Inductive Load, Dale NHL-100-06N or equivalent.
(5) Variac, 240V, 3.5 A, Staco 3PN1020 or similar means to
produce 90 to 264VAC, 50 and 60Hz power at 200W or greater.
(6) HiPot Tester, Biddle type 230415 or equal.
(7) Leakage Current Tester Arrangement, see Figure 3.9.
(8) Ground Bond Tester (A properly programmed comprehensive safety analyzer can replace items (6), (7) and (8).)
B Alarm Test
(1) Connect unit under test with attached footswitch, output cable, dispersive electrode and line cord as shown in Figure 3.3.
(2) Set line input voltage to the nominal value of AC appropriate for the model being tested.
(3) Switch the power switch to on (“|”). Verify the green POWER indicator illuminates.
(4) With the output control knob set to “0” press the footswitch and adjust the sound level by adjusting R38 to read 4.5Vp-p across the speaker terminals on J4.
(5) Disconnect the Dispersive Electrode. Verify the red ALARM indicator illuminates.
(6) Connect the 600 Ohm load to the output. With the power control set at “0”, press the footswitch. Verify the unit emits a warbling alarm sound.
(7) With the power control set at full CUT “6”, press the footswitch.
Verify that in addition to the red indicator and warbling sound the RF output is less than 10mW into a 600 Ohm non-inductive load.
(8) Repeat test (6) with the power control set at full COAG “6”.
Disconnect the 600 Ohm load. Reconnect the Dispersive Electrode.
C Unloaded Output Test
(1) Connect unit under test with attached footswitch, output cable, Dispersive Electrode and line cord as shown in Figure 3.3.
(2) Set line input voltage to the nominal value of AC appropriate for the model being tested.
(3) Turn on power to the unit. Verify the green POWER indicator illuminates.
(4) With the power control set at “CUT 2”, press the footswitch momentarily and verify yellow active indicator illuminates and a 400 Hz tone is produced. The blue indicator shall not illuminate.
(5) Set CUT/COAG intensity control to full right position (CUT position).
(6) Press the footswitch and verify the Cut Mode waveform is in accordance with Figure 3.4.
(7) Set CUT/COAG intensity control to full left position (COAG position).
(8) Press footswitch and verify Coag Mode waveform is in accordance with Figure 3.5 and the blue active indicator is
illuminated and a 400 Hz tone is produced. The yellow indicator shall not illuminate.
(9) While pressing footswitch, slowly move CUT/COAG intensity control from full left COAG “6" position to COAG "1" position and verify voltage level of COAG Mode waveform gradually
decreases to 575 ±100 volts p-p.
(10) While pressing footswitch, slowly move CUT/COAG intensity control from center detent position to full right position (CUT) and verify voltage level of CUT Mode waveform gradually increases to 770 ±120 volts p-p.
D Tuning Adjustment
(1) Connect unit under test as shown in Figure 3.6. Ensure line voltage is set to the nominal AC value appropriate for the model being tested. Be sure the oscilloscope probe is properly
compensated to obtain correct readings. Apply power.
(2) Set CUT/COAG intensity control to full right position (CUT position).
(3) Press footswitch and verify that oscilloscope reading is 513 ±25 volts p-p or that the ammeter reading is 303 ±13 mA.
(4) If the reading is out of tolerance, adjust ferrite tuning screw in L2 with a non-metallic tool to obtain the required reading.
E Loaded Output Test
(1) Connect unit under test as shown in Figure 3.6. Ensure line voltage is set to the nominal AC value appropriate to the model being tested. Be sure the oscilloscope probe is properly
compensated to obtain correct readings.
(2) Set CUT/COAG intensity control to full right position (CUT position).
(3) Press footswitch and verify that oscilloscope reading is 514 ±23 volts p-p.
(4) Repeat step (3) with line voltage set to 90% of nominal value.
(5) Repeat step (3) with line voltage set to 110% of nominal value.
(6) Set line voltage to nominal AC value.
(7) Set CUT/COAG intensity control to full left position (COAG position).
(8) Measuring the output power in the COAG mode with an
oscilloscope is more complicated because the voltage across the load resistor is no longer directly indicative of the power. The simple continuous power obtained from P = E2/R must be multiplied by the measured duty cycle of the signal [ratio of ON/(ON+OFF)], yielding the actual modulated signal power in the load resistor. Refer to Figure 3.5 for a representation of the COAG modulated signal.
(9) Press footswitch and verify that the load resistor p-p voltage measured with an oscilloscope is 532 ±27 volts p-p and that the duty cycle is 0.5 ±0.1.
(10) Repeat step (8) with line voltage set to 90% of nominal value.
(11) Repeat step (8) with line voltage set to 110% of nominal value.
(12) Set line voltage to the nominal AC value.
(13) Set CUT/COAG intensity control to minimum CUT mode position ("1"). (Adjust slightly higher if necessary to activate output.)
(14) Press footswitch and verify that oscilloscope reading is 367 ±19 volts p-p.
(15) Repeat step (13) with line voltage set to 90% of nominal value.
(16) Repeat step (13) with line voltage set to 110% of nominal value.
(17) Set CUT/COAG intensity control to "0" position.
(18) Press footswitch and verify there is no output indicated by the oscilloscope but the 400 Hz audio tone is produced.
F Dielectric Voltage Withstand Tests
(1) Connect unit under test as shown in Figure 3.7.
(2) Place power switch in ON position (“|” position).
(3) Set HiPot tester for an output of 1776 volts RMS for a period of one (1) second and verify a breakdown does not occur.
(4) Connect unit under test as shown in Figure 3.8 (ensure POWER switch is in on position).
(5) Set HiPot tester for an output of 3000 volts RMS for a period of one (1) second and verify a breakdown does not occur.
WARNING!
Stay clear of the unit and all connecting cables
while voltage is applied during this
test!
G Ground Leakage Test
(1) Connect unit under test as shown in Figure 3.9 (ensure switches S3 and S1 are in the open position. switch S2 is in the A
position. and unit under test line cord is not mated with power receptacle).
(2) Set input voltage to nominal AC value +10%.
(3) Ensure unit under test POWER switch is in the on position (do not activate the unit for this test.
(4) Connect unit under test line cord plug to power receptacle.
(5) Measure leakage voltage by placing voltmeter probe on metal contact of unit under test (such as outer shell of handpiece connector).
(6) Convert measured leakage voltage to leakage current using the following formula:
(7) Leakage Current = Leakage Voltage /1000
(8) Calculated leakage current should not exceed 1000 µA (0.001A). (9) Repeat steps (5) and (6) for each of the switch settings below
(Note maximum allowable leakage current for each of the settings):
SWITCH SETTINGS LEAKAGE CURRENT